Medical practice is roughly divided into two areas: diagnostics service and treatment service.
The diagnostics service has an objective of obtaining the name and state of a disease, and thus a treatment regimen is determined according to the disease name and the disease state. In order to determine the disease name or the disease state, pathological diagnostics is performed by taking a specimen from a lesion and observing the state on a cellular level. In the pathological diagnostics, the obtained specimen is sliced to a thickness that can be observed with a microscope to give a sample. The sample is captured with a digital camera or a scanner through the microscope, and the resulting digital image is stored and referenced.
Digitization of diagnostic images as described above has brought increased consistency with computerized data processing, and thus has provided more opportunities to assist physicians and technicians with their diagnostics service by using IT systems. CAD (Computer Aided Detection) is an example of such digitalization, and is a method of utilizing a computer in detection of a lesion.
However, when scanners or cameras for capturing images of samples have different input characteristics, a plurality of different sample images are produced from a single sample. The pathological diagnostics is performed by observing a stained sample, and thus differences in color affect the diagnostic results. For example, in the method disclosed in Patent Literature (PTL) 1, situations arise in which the pixels defining an object of interest, the pixels defining a normal cell, and the pixels defining the background area of a biological specimen image vary depending on the scanners or the cameras. Accordingly, it is not possible to uniquely determine threshold values for identifying the object of interest, the normal cell and the background, and thus it is necessary to set threshold values for each scanner or camera. However, setting threshold values in each scanner or camera is inefficient in terms of maintenance of the image measurement apparatus.
Under the circumstances described above, PTL 2 discloses a technique for performing accurate pathological diagnostics by correcting differences in the input characteristics of scanners or cameras for capturing images of samples.